1. Field of the Invention
The present invention is related, in general, to packaged semiconductor devices, in particular, to heatsink structure of packaged semiconductor devices.
2. Description of the Related Art
In order to achieve efficient heat release, packaged semiconductor devices often adopt heatsink structure that allows heat release from both of the main and rear surfaces of semiconductor chips.
A packaged semiconductor device adopting such heatsink structure is disclosed in Japanese Unexamined Patent Application No. P2002-164485A. FIG. 1 shows the structure of the disclosed semiconductor device. The disclosed semiconductor device is composed of first and second insulating substrate 102 and 104 of aluminum nitride, which is highly thermally conductive, and first and second heatsinks 103 and 105 respectively connected to the first and second insulating substrate 102 and 104. This heatsink structure allows heat release from the main surface of a semiconductor chip 101 through the first insulating substrate 102 and the heatsink 103, while allowing heat release from the rear surface of the semiconductor chip 101 through the second insulating substrate 104 and the heatsink 105. The electrical connection between the semiconductor chip 101 and an external world is achieved by interconnections disposed on the insulating substrate 102, conductors 106 connected to the interconnections, bonding wires 107, and terminals 108.
Other heatsink structures allowing heat release from both of the main and rear surfaces of semiconductor chips are disclosed in Japanese Unexamined Patent Applications No. Jp-A-Heisei 7-29940, Jp-A-Heisei 8-64730, and P2000-174180A.
It would be advantageous if semiconductor device packages have an improved heat release efficiency.
It would be also advantageous if lengths of interconnections provided for semiconductor device packages to achieve are reduced. Shortened interconnections of semiconductor device packages effectively reduce signal delays therein, and also avoids impedance mismatching for high frequency signals.